dna

(redirected from heteroduplex DNA)
Also found in: Dictionary, Thesaurus, Medical, Encyclopedia, Wikipedia.

DNA

n. scientifically, deoxyribonucleic acid, a chromonal double chain (the famous "double helix") in the nucleus of each living cell the combination of which determines each individual's hereditary characteristics. In law, the importance is the discovery that each person's DNA is different and is found in each living cell, so a hair, blood, skin or any part of the body can be used to identify and distinguish an individual from all other people. DNA testing can result in proof of one's involvement or lack of involvement in a crime scene. While recent DNA tests have proved a convicted killer on death row did not commit a crime and resulted in his release, current debate concerns whether DNA evidence is scientifically certain enough to be admitted in trials. The trend is strongly in favor of admission.

dna

noun authentication, certification, confirmation of identity, proof of identity, scientific evidence, scientific means of designation, scientific means of identity, scientific means to distinguish a person, scientific method to reveal identity, substantiation, validation of identity, verification of identity, deoxyribonucleic acid
Associated concepts: appeal of a case, DNA fingerprint, DNA polymerase, forensics, overturning a case, reversal of a case

DNA

abbreviation for deoxyribonucleic acid, a chemical which is found in virtually every cell in the body and which carries genetic information. Except for identical twins, each person's DNA is unique. DNA profiling doesn't allow the examination of every single difference between people's DNA so the concentration will be on those aspects which are most likely to yield a difference. DNA can be extracted from any cells that contain a structure called the nucleus, for example, blood, semen, saliva or hair.

Mitochondrial DNA is inherited only from a person's mother. Brothers and sisters have the same mitochondrial DNA type as their mother. This feature of mitochondrial DNA can be used for body identification. The γ-chromosome is present only in men and is largely unchanged as it passes through the male line of a family. The usefulness of the technique in criminal matters is vastly enhanced by the extent to which it is possible to compare a sample with other individuals. To this end there is a National DNA Database maintained by the ASSOCIATION OF CHIEF POLICE OFFICERS and managed by the FORENSIC SCIENCE SERVICE. Techniques vary. There is a UK offence of DNA theft. It is also of assistance in paternity matters.

References in periodicals archive ?
First, this individual and her progeny enabled us to observe the appearance of heteroduplex DNA created in PCR amplification of the ITS-1 diagnostic marker from an interspecific hybrid (Fig.
In addition, it is well suited for the analysis of heterozygous patients because it is based on the formation of heteroduplex DNA, which is easily separated from homoduplex DNA by HPLC.
The PCR product is amplified, melted, and reannealed to generate a mixture of homo- and heteroduplex DNA, which is melted in an analytical melting cycle.
In this variation of HDA, the lower melting temperature of heteroduplex DNA molecules containing mismatches relative to the homoduplex molecules was exploited to partially denature the DNA during electrophoresis.
A difference in the thermodynamic stability of heteroduplex DNA directly explains the improved efficiency of gel-based methods such as DGGE to detect sequence variations by comparison of a heteroduplex DNA with component homoduplex DNAs.